Northern and Southern Dynasties

The Northern and Southern Dynasties was the period of Chinese history from 439 to 589 AD during which China was divided between competing northern and southern dynasties. The era followed Northern Wei's unification of northern China at the end of the Sixteen Kingdoms era and ended when the Sui dynasty briefly united China.

Northern Dynasties
In 439, the Northern Wei conquered Northern Liang, unifying northern China. The Xianbei founders of Northern Wei underwent Sinicization, adopting the Chinese surname "Yuan"; in 493 AD, under Emperor Xiaowen of Northern Wei, the Xianbei elite was commanded to wear Chinese clothing, learn the Chinese language if under the age of thirty, adopt one-character Chinese surnames, and marry into Chinese families. In 523 AD, a food shortage led to the rebellion of several Northern Wei garrisons far north of Luoyang, and the government crushed the uprising and sent the 200,000 captured rebels to Hebei. In 526-527, these rebels rose in rebellion under a new officer, and they murdered the young Emperor, leading to a civil war between Eastern Wei and Western Wei. The general Gao Huan made Emperor Xiaojing of Eastern Wei his puppet ruler, and his son Gao Yang overthrew the puppet emperor in 551 and became "Emperor Wenxuan of Northern Qi", establishing the state of Northern Qi. The son of Gao Huan's rival Yuwen Tai, Yuwen Jue, went on to overthrow Eastern Wei and create the Northern Zhou dynasty. In 577, the Northern Zhou conquered Northern Qi, only for the Northern Zhou to be overthrown by the nascent Sui dynasty in 581.

Southern Dynasties
Meanwhile, Liu Song unified southern China after overthrowing the Eastern Jin, and the Northern Wei and Liu Song competed to unify China. Liu Song was marred by a series of paranoid, kinslaying emperors, and, in 479, the general Xiao Daocheng overthrew the Liu Song dynasty and became "Emperor Gao of Southern Qi". His grandsons were usurped and killed by their relative Xiao Luan, who crowned himself "Emperor Ming of Southern Qi". The Xiao family's civil wars culminated in Xiao Yan overthrowing the Southern Qi and establishing the Later Liang, becoming known as Emperor Wu of Liang. The Liang also went to war with Wei, and Eastern Wei general Hou Jing succeeded in conquering Jiankang. Western Wei later set up the puppet state of Western Liang during their own war with Liang, and Northern Qi later invaded Liang and set up a puppet emperor. Chen Baxian then deposed the puppet emperor and declared himself Emperor Wu of Chen in 557, founding the Chen dynasty. The Chen allied with Northern Zhou to defeat Northern Qi, but, in 577, Northern Zhou took advantage of Northern Qi's weakness to attack Chen and reconquer lands to the south of the Huai River. After Zhou was overthrown by Yang Jian, the first Sui emperor, the Sui invaded Chen and finally vanquished it from 588 to 589, when they captured Jiankang. The fall of Jiankang marked the end of the Chen dynasty and the Sui dynasty's unification of China.